The Therapeutic Effects Of Vibratory Stimulation
The therapeutic effects of vibratory stimulation on the human body have been well documented. Vibration applied to tissue increases blood circulation due to the increase in capillary dilation. The increased blood flow increases the consumption of oxygen and nutrients by muscles and improves the regeneration process. The result is an improved muscular tone, elasticity and contractile capacity. In addition, vibratory stimulation reduces tissue swelling, enhances healing of wounds and results in effective anti-inflamatory action.
The physiological effect of low frequency vibratory stimulation varies depending on the frequency, amplitude and duration of its application. Depending on the structure of the muscles (smooth or straiated), the same dose of local vibratory stimulation may cause either contraction or relaxation. A low frequency mechanical vibration of between 60 and 200 Hz applied to skeletal muscle induces a sustained contraction of the muscle and a simultaneous relaxation of its prime antagonists. This tonic vibratory reflex (TVR) is elicited in normal, spastic, paretic and myotonic muscles alike. Within the 60 to 200 Hz range, the vibration reduces the contractile force and tension of smooth muscle.
The most common therapeutic uses of vibratory stimulation involve external application of the vibratory forces. Vibratory stimulation is used for treating neuromuscular motor dysfunction in patients with cerebral palsy. External vibration is also used for treating patients with cervical osteochondrosis, lumbosacral radiculitis, postamputation contracture, sequelae of lesions of the long tubular bones, and chronic dental pain. Externally applied abdominal vibration is used for improving efficiency in peritoneal dialysis and for stimulating intestinal mobility in cases of intestinal atonia. External vibratory stimulation is also useful for bladder voiding in paralyzed patients.
Vibratory stimulation has also been used internally to relax and dilate the cervix prior to abortion or birth. Vibration accelerates expansion of the cervical opening, thereby facilitating parturition. The vibration is applied directly to the cervical muscle, and the source of the vibration is withdrawn as soon as the cervical dilation is achieved.
Vibration sources vary with the application. External vibration may be applied by large flat or rounded vibrating machines designed to be placed against the appropriate body parts. Internal vibratory stimulation of the cervix, on the other hand, may be applied by a vibrating spatula or a vibrating bullet shaped applicator placed against the wall of the cervical muscle.
Internally applied vibratory stimulation has not been used, however, for treating internal muscle and connective tissue disorders such as urethral strictures, urinary and anal incontinence, unstable bladder, and urethral syndrome. The prior art methods of treating such disorders is discussed below.
Urethral Strictures
Urethral strictures, especially posttraumatic ones, are very dense, rigid, and resistant to stretching. They are localized mostly in the membranous or bulbous parts of the urethra. A non-surgical method for treating urethral strictures, known as bougienage, involves probing such strictures with elongated members or probes to enlarge them.
Such probes are known as bougies. Conventional bougies are shown in the text "Urology", 3d ed., v.1, p. 242, M. F. Campbell and J. H. Harrison, eds. (Saunders, 1970). Such bougies are solid metal or plastic rods which are shaped to accommodate the physiological curvature of the urethra. In males the urethra's outer part is within the highly flexible pendulus of the penis and can be bent or straightened as necessary. The urethra's inner part extends around the pubic articulation and is therefore curved. Thus, conventional bougies generally comprise a straight portion extending from the handle, followed by a curved portion adjacent the tip. This shape corresponds to the urethra when the penis is straightened.
Despite the correspondence in shapes, the insertion of a conventional bougie in males is a very complicated and painful operation, requiring high skill and concentration. Usually, the urologist will employ a set of bougies of gradually increasing diameter. The results of treatment with such instruments are not always positive; complications such as bleeding, perforations of the urethral wall and other injuries, urinary fever, prostatitis, epididymitis, and the like may occur. Even in females, whose urethras are shorter and straighter, many of these difficulties are encountered. Moreover, the conventional bougie is used only for dilation and cannot be utilized for vibratory stimulation.
Urinary Incontinence
Urinary incontinence is a distressing and previously neglected condition which can result from a range of pathological processes in the central or peripheral nervous system, the bladder, or the urethra. The disorder is related to faulty storage or deficient control and is difficult to treat.
Incontinence can affect all ages. Several reports have shown that 16-50% of nonparous females admit to the loss of a small amount of urine during hard coughing, laughing, or sneezing, particularly if the bladder is excessively full. Five percent of women between the ages of 15-34 and about 10 to 26% in ages of 35-60 reported regular troublesome stress urinary incontinence. As is shown by both European and American researchers, urinary incontinence is a problem affecting 10 to 40% of the elderly women in the community and up to 50% of the elderly in institutions. Urinary incontinence is therefore a major geriatric problem with substantial medical and social implications.
Stress urinary incontinence is defined as the involuntary loss of urine through the intact urethra as the result of a sudden increase in intra-abdominal pressure in the absence of bladder activity. Stress urinary incontinence accounts for roughly 75% of all female urinary incontinence.
The most frequent cause of stress urinary incontinence in females is the poor function of the sphincteric mechanism of the urethra and an inadequate pelvic floor function. The key factor in the development of stress incontinence in females is an inherent weakness in the mechanism of urinary continence upon which precipitating factors exert influence. Typically the problem occurs in women in whom childbirth causes long-term anatomic damage and a relaxation in the pelvic and periurethral musculature. The percentage of such women comprises about 52.2% of the total number of stress urinary incontinence sufferers.
Menopause is another very important precipitating factor in the development of stress incontinence. Hormonal dysfunction in postmenopausal women is characterized by estrogen deficiency and leads to atrophy of pelvic tissues. This can distort local anatomy and result in stress incontinence.
Involuntary detrusor contractions are also a common cause of urinary frequency, urgency, nocturia, bed wetting, urge incontinence, and the like. Abnormalities of detrusor contraction may be of myogenic, neurogenic, or psychoplogic origin. In the absence of a neurologic lesion, the condition is termed "detrusor instability." The unstable bladder is a very common problem affecting as much as 10% of the population and a substantially higher percentage at the two extremes of life. In most cases the etiology of the detrusor instability remains unknown, since these patients are referred to as having "idiopathic" detrusor instability. As a result, the treatment of detrusor instability is difficult.
Conventional treatment of urinary incontinence falls into four main categories: surgery, drug therapy, re-education, and, where necessary, the use of protective clothing, tampons, vaginal appliances designed to support the urethra, and indwelling catheters. These treatments are discussed below.
There are over 50 surgical procedures designed to correct urinary incontinence. The success of these procedures, however, is much higher in younger women than in the elderly. Approximately 10-40% of women who undergo surgical correction of urinary stress incontinence will have recurrent urinary incontinence and other voiding difficulties. Surgery is not effective when the problem is an unstable bladder or intrinsic urethral abnormalities, and the condition of the patient after surgery in this case can worsen.
The surgical method is generally accepted as the most appropriate treatment for severe female genuine stress incontinence. In a number of cases, this method is also used for treating patients with a mild-to-moderate form of incontinence.
The trend in the profession, however, is to avoid surgical therapy if possible. In addition, there are some patients for whom surgery is inappropriate. For example, women who wish further pregnancies would be poor candidates since later vaginal deliveries may adversely affect successful surgery.
New surgical techniques such as electronic stimulation of sphincters and implantations of artificial sphincters are widely used for treating patients with urinary incontinence caused by surgical traumas or by organic neurologic dysfunctions. Although these new methods give promising results, they still require further clinical studies as well as improvements in devices necessary for implementation of these methods.
Drugs of several types also have been recommended for treating stress urinary incontinence. These drugs are nonspecific, however, and therefore act on structures and viscera other than the bladder and urethra. Large doses are often required, and toxicity can easily be reached before the desired effect on the bladder and urethra is achieved. Moreover, even when drug treatment is effective, it does not lead to restoration of a normal micturition pattern.
Re-education for incontinence includes bladder retraining programs and re-education of the pelvic floor muscles. The bladder re-training method consists of instituting a program of scheduled voidings with a progressive increase in the interval between each micturition. A four to six week treatment program is common.
Two different methods of electrical stimulation for the correction of urinary incontinence are in use and are classified according to the time of application and the intensity of electrical stimuli: long-term, or chronic, electrical stimulation and short-term, or maximum, electrical stimulation. Long-term electrical stimulation is continued 6-20 hours daily for prolonged periods of from 3 to 36 months and short-term, or maximum, electrical stimulation is continued 20-30 minutes over a one-month period, the stimulation being applied 1-5 times a day. Electrostimulation has been found to be valuable in cases of urinary urge incontinence due to detrusor instability since it is more effective than drug treatment and can produce re-education of incontinence. The mechanisms behind this curative effect are not yet defined, however.
Exercise therapy, which is a natural biological and non-invasive functional method of treatment, plays a leading role in non-surgical methods of treatment of stress urinary incontinence, as this method positively effects a weakened muscular-ligamentous apparatus of the pelvic floor. The exercise is designed to strengthen the urethral and periurethral striated muscles. Physiotherapy consists of four or five pelvic floor contractions repeated every hour and interrupted micturition practiced on each occasion. In the beginning, the treatment is carried out on a hospital basis for four weeks followed by self-treatment for a prolonged period of time.
As a rule, all the non-surgical methods of treatment of urinary incontinence described above are lengthy and required repeated courses of treatment. In addition, the long-term results of these types of treatment are largely unsuccessful. In spite of a large number of investigations dedicated to urinary incontinence, this problem is still far from being resolved.
Urethral Syndrome
Urethral syndrome is a condition indicating lower urinary tract symptoms, such as frequency and dysuria in the absence of obvious bladder or urethral abnormality where the urine is sterile or contains less than 10.sup.5 microorganisms per mL. Urethral syndrome has been estimated to occur in 20-30% of all adult females.
One cause of urethral syndrome is extra-urethral pathology which is revealed in the form of changes in connective tissues between the urethra and the vagina (the urethrovaginal septum). This is expressed in an increased amount of collagenous tissue in the abovementioned area which, in turn, may lead to obstruction. Thus, vaginitis can produce dysuria and frequency by contingous involvement of the periurethral area.
Because urethral syndrome is caused by many different etiologic factors, the treatment of this condition is difficult. Treatment modalities range from an operative technique to a local application of silver nitrate, antibiotics, estrogens and steriods, as well as psychotherapy.
Urethral dilation and manual massage has been recommended as treatment for urethral syndrome. Such treatment is typically performed with a rigid surgical instrument on which intravaginal massage of the urethral wall can be performed.
Abnormally high and varying tensions within the voluntary sphincter of the urethra and cardinal functional changes produces the urethral syndrome in women. When spasm is found as the cause of urethral syndrome, both smooth and skeletal muscle relaxants have been given for the relief of symptoms. Unfortunately, repeated courses of this treatment often have little therapeutic value. Urethral dilation is also less effective in these patients.
After a physiological menopause, hypoestrogenism occurs and retrogressive (senile) changes take place in the vaginal and urethral mucosa. The treatment of urethral syndrome secondary to hypoestrogenism is oral and topical vaginal estrogen.
In spite of a great number of reports dedicated to this subject, a considerable number of problems relating to etiology, pathogenesis, and treatment as yet remain unsolved. Irrespective of long-termed and repeated courses of treatment, urethral syndrome often recurs.
Object of the Invention
The existing methods for treating the internal muscle and connective tissue disorders discussed above have proved to be inadequate. Therefore, a more effective method and apparatus to treat these and other internal disorders is needed. Thus, the main object of this invention is to provide an apparatus and method for the vibratory treatment of internal muscle and connective tissue disorders.